On Thu 21 Feb 04:18 PST 2019, Laurent Pinchart wrote:
> Hi Vaishali,
>
> Thank you for the patch.
>
> On Wed, Feb 20, 2019 at 10:28:29AM +0530, Vaishali Thakkar wrote:
> > The Qualcomm socinfo provides a number of additional attributes,
> > add these to the socinfo driver and expose them via debugfs
> > functionality.
>
> What is the use case for these attributes ? I fear they will be used in
> production systems, and that would require debugfs in production, which
> isn't a good idea. If you need to expose those attributes for anything
> else than debugging then we need a proper API, likely sysfs-based.
>
The use case of these attributes, beyond development/debugging, are
unfortunately somewhat unknown and is the reason why they where moved to
debugfs from the earlier attempts to upstream this.
I think the production requirements at hand prohibits debugfs to be
present, so attributes that are required beyond development/debugging
purposes would have to be migrated out to sysfs - but the idea here is
that such migration would have come with the missing motivation to add
them there today.
Regards,
Bjorn
> > Signed-off-by: Vaishali Thakkar <vaishali.thak...@linaro.org>
> > ---
> > Changes since v1:
> > - Remove unnecessary debugfs dir creation check
> > - Align ifdefs to left
> > - Fix function signatures for debugfs init/exit
> > ---
> > drivers/soc/qcom/socinfo.c | 198 +++++++++++++++++++++++++++++++++++++
> > 1 file changed, 198 insertions(+)
> >
> > diff --git a/drivers/soc/qcom/socinfo.c b/drivers/soc/qcom/socinfo.c
> > index 02078049fac7..5f4bef216ae1 100644
> > --- a/drivers/soc/qcom/socinfo.c
> > +++ b/drivers/soc/qcom/socinfo.c
> > @@ -4,6 +4,7 @@
> > * Copyright (c) 2017-2019, Linaro Ltd.
> > */
> >
> > +#include <linux/debugfs.h>
> > #include <linux/err.h>
> > #include <linux/module.h>
> > #include <linux/platform_device.h>
> > @@ -29,6 +30,28 @@
> > */
> > #define SMEM_HW_SW_BUILD_ID 137
> >
> > +#ifdef CONFIG_DEBUG_FS
> > +/* pmic model info */
> > +static const char *const pmic_model[] = {
> > + [0] = "Unknown PMIC model",
> > + [9] = "PM8994",
> > + [11] = "PM8916",
> > + [13] = "PM8058",
> > + [14] = "PM8028",
> > + [15] = "PM8901",
> > + [16] = "PM8027",
> > + [17] = "ISL9519",
> > + [18] = "PM8921",
> > + [19] = "PM8018",
> > + [20] = "PM8015",
> > + [21] = "PM8014",
> > + [22] = "PM8821",
> > + [23] = "PM8038",
> > + [24] = "PM8922",
> > + [25] = "PM8917",
> > +};
> > +#endif /* CONFIG_DEBUG_FS */
> > +
> > /* Socinfo SMEM item structure */
> > struct socinfo {
> > __le32 fmt;
> > @@ -70,6 +93,10 @@ struct socinfo {
> > struct qcom_socinfo {
> > struct soc_device *soc_dev;
> > struct soc_device_attribute attr;
> > +#ifdef CONFIG_DEBUG_FS
> > + struct dentry *dbg_root;
> > +#endif /* CONFIG_DEBUG_FS */
> > + struct socinfo *socinfo;
> > };
> >
> > struct soc_of_id {
> > @@ -133,6 +160,171 @@ static const char *socinfo_machine(struct device
> > *dev, unsigned int id)
> > return NULL;
> > }
> >
> > +#ifdef CONFIG_DEBUG_FS
> > +
> > +#define UINT_SHOW(name, attr)
> > \
> > +static int qcom_show_##name(struct seq_file *seq, void *p) \
> > +{ \
> > + struct socinfo *socinfo = seq->private; \
> > + seq_printf(seq, "%u\n", le32_to_cpu(socinfo->attr)); \
> > + return 0; \
> > +} \
> > +static int qcom_open_##name(struct inode *inode, struct file *file)
> > \
> > +{ \
> > + return single_open(file, qcom_show_##name, inode->i_private); \
> > +} \
> > + \
> > +static const struct file_operations qcom_ ##name## _ops = {
> > \
> > + .open = qcom_open_##name, \
> > + .read = seq_read, \
> > + .llseek = seq_lseek, \
> > + .release = single_release, \
> > +}
> > +
> > +#define DEBUGFS_UINT_ADD(name)
> > \
> > + debugfs_create_file(__stringify(name), 0400, \
> > + qcom_socinfo->dbg_root, \
> > + qcom_socinfo->socinfo, &qcom_ ##name## _ops)
> > +
> > +#define HEX_SHOW(name, attr)
> > \
> > +static int qcom_show_##name(struct seq_file *seq, void *p) \
> > +{ \
> > + struct socinfo *socinfo = seq->private; \
> > + seq_printf(seq, "0x%x\n", le32_to_cpu(socinfo->attr)); \
> > + return 0; \
> > +} \
> > +static int qcom_open_##name(struct inode *inode, struct file *file)
> > \
> > +{ \
> > + return single_open(file, qcom_show_##name, inode->i_private); \
> > +} \
> > + \
> > +static const struct file_operations qcom_ ##name## _ops = {
> > \
> > + .open = qcom_open_##name, \
> > + .read = seq_read, \
> > + .llseek = seq_lseek, \
> > + .release = single_release, \
> > +}
> > +
> > +#define DEBUGFS_HEX_ADD(name)
> > \
> > + debugfs_create_file(__stringify(name), 0400, \
> > + qcom_socinfo->dbg_root, \
> > + qcom_socinfo->socinfo, &qcom_ ##name## _ops)
> > +
> > +
> > +#define QCOM_OPEN(name, _func)
> > \
> > +static int qcom_open_##name(struct inode *inode, struct file *file)
> > \
> > +{ \
> > + return single_open(file, _func, inode->i_private); \
> > +} \
> > + \
> > +static const struct file_operations qcom_ ##name## _ops = {
> > \
> > + .open = qcom_open_##name, \
> > + .read = seq_read, \
> > + .llseek = seq_lseek, \
> > + .release = single_release, \
> > +}
> > +
> > +#define DEBUGFS_ADD(name) \
> > + debugfs_create_file(__stringify(name), 0400, \
> > + qcom_socinfo->dbg_root, \
> > + qcom_socinfo->socinfo, &qcom_ ##name## _ops)
> > +
> > +
> > +static int qcom_show_build_id(struct seq_file *seq, void *p)
> > +{
> > + struct socinfo *socinfo = seq->private;
> > +
> > + seq_printf(seq, "%s\n", socinfo->build_id);
> > +
> > + return 0;
> > +}
> > +
> > +static int qcom_show_accessory_chip(struct seq_file *seq, void *p)
> > +{
> > + struct socinfo *socinfo = seq->private;
> > +
> > + seq_printf(seq, "%d\n", le32_to_cpu(socinfo->accessory_chip));
> > +
> > + return 0;
> > +}
> > +
> > +static int qcom_show_platform_subtype(struct seq_file *seq, void *p)
> > +{
> > + struct socinfo *socinfo = seq->private;
> > + int subtype = le32_to_cpu(socinfo->hw_plat_subtype);
> > +
> > + if (subtype < 0)
> > + return -EINVAL;
> > +
> > + seq_printf(seq, "%u\n", subtype);
> > +
> > + return 0;
> > +}
> > +
> > +static int qcom_show_pmic_model(struct seq_file *seq, void *p)
> > +{
> > + struct socinfo *socinfo = seq->private;
> > + int model = SOCINFO_MINOR(le32_to_cpu(socinfo->pmic_model));
> > +
> > + if (model < 0)
> > + return -EINVAL;
> > +
> > + seq_printf(seq, "%s\n", pmic_model[model]);
> > +
> > + return 0;
> > +}
> > +
> > +static int qcom_show_pmic_die_revision(struct seq_file *seq, void *p)
> > +{
> > + struct socinfo *socinfo = seq->private;
> > +
> > + seq_printf(seq, "%u.%u\n",
> > + SOCINFO_MAJOR(le32_to_cpu(socinfo->pmic_die_rev)),
> > + SOCINFO_MINOR(le32_to_cpu(socinfo->pmic_die_rev)));
> > +
> > + return 0;
> > +}
> > +
> > +UINT_SHOW(raw_version, raw_ver);
> > +UINT_SHOW(hardware_platform, hw_plat);
> > +UINT_SHOW(platform_version, plat_ver);
> > +UINT_SHOW(foundry_id, foundry_id);
> > +HEX_SHOW(chip_family, chip_family);
> > +HEX_SHOW(raw_device_family, raw_device_family);
> > +HEX_SHOW(raw_device_number, raw_device_num);
> > +QCOM_OPEN(build_id, qcom_show_build_id);
> > +QCOM_OPEN(accessory_chip, qcom_show_accessory_chip);
> > +QCOM_OPEN(pmic_model, qcom_show_pmic_model);
> > +QCOM_OPEN(platform_subtype, qcom_show_platform_subtype);
> > +QCOM_OPEN(pmic_die_revision, qcom_show_pmic_die_revision);
> > +
> > +static void socinfo_debugfs_init(struct qcom_socinfo *qcom_socinfo)
> > +{
> > + qcom_socinfo->dbg_root = debugfs_create_dir("qcom_socinfo", NULL);
> > +
> > + DEBUGFS_UINT_ADD(raw_version);
> > + DEBUGFS_UINT_ADD(hardware_platform);
> > + DEBUGFS_UINT_ADD(platform_version);
> > + DEBUGFS_UINT_ADD(foundry_id);
> > + DEBUGFS_HEX_ADD(chip_family);
> > + DEBUGFS_HEX_ADD(raw_device_family);
> > + DEBUGFS_HEX_ADD(raw_device_number);
> > + DEBUGFS_ADD(build_id);
> > + DEBUGFS_ADD(accessory_chip);
> > + DEBUGFS_ADD(pmic_model);
> > + DEBUGFS_ADD(platform_subtype);
> > + DEBUGFS_ADD(pmic_die_revision);
> > +}
> > +
> > +static void socinfo_debugfs_exit(struct qcom_socinfo *qcom_socinfo)
> > +{
> > + debugfs_remove_recursive(qcom_socinfo->dbg_root);
> > +}
> > +#else
> > +static void socinfo_debugfs_init(struct qcom_socinfo *qcom_socinfo) {
> > return 0; }
> > +static void socinfo_debugfs_exit(struct qcom_socinfo *qcom_socinfo) { }
> > +#endif /* CONFIG_DEBUG_FS */
> > +
> > static int qcom_socinfo_probe(struct platform_device *pdev)
> > {
> > struct qcom_socinfo *qs;
> > @@ -165,6 +357,10 @@ static int qcom_socinfo_probe(struct platform_device
> > *pdev)
> > if (IS_ERR(qs->soc_dev))
> > return PTR_ERR(qs->soc_dev);
> >
> > + qs->socinfo = info;
> > +
> > + socinfo_debugfs_init(qs);
> > +
> > /* Feed the soc specific unique data into entropy pool */
> > add_device_randomness(info, item_size);
> >
> > @@ -179,6 +375,8 @@ static int qcom_socinfo_remove(struct platform_device
> > *pdev)
> >
> > soc_device_unregister(qs->soc_dev);
> >
> > + socinfo_debugfs_exit(qs);
> > +
> > return 0;
> > }
> >
>
> --
> Regards,
>
> Laurent Pinchart
